Problem: Nadia starts counting at 42, and she counts by fours. If 42 is the 1st number that Nadia counts. what is the 11th number that she counts?
Answer: What is the first number that she counts? $42$ What is the second number that she counts? $\begin{align*}&42 + 4 \\ &= 46\end{align*}$ What is the third number that she counts? $\begin{align*}&42 + 4 + 4 \\ &= 42 + (2 \times 4) \\ &= 50\end{align*}$ What is the 11th number that she counts? $\begin{align*}&42 + (10\times4) \\ &= 42 + 40 \\ &= 82\end{align*}$